The femoral veins were excised from 28 dogs and distended with pressure of 40, 80 and 120 kPa, respectively before grafted to femoral arteries. The veins were harvested at different times and Pollak sections were prepared which revealed different stains of elastin, collagen and smooth muscle in each section. The sections were led to image analysis system to computerize the relative contents of theabove components. The results were as follows: Elastin decreased significantly at 4 weeks (P lt;0.01), and was constant between 4 and 16 weeks. No statistical difference was found in 40, 80 kPa and the control group (P gt;0.05), but the elastin of 120 kPa group by the 16th week was still decreasing. Collagen of each group had no difference, but C/E increased significantly with time. Smooth muscle contents were correlated positively with time, and negatively with the pressure at 1 week, then positively with the pressure at 16th week. The changes of the above trends were the same as development of intimal hyperplasia. The contentions were the value of C/E was determined by the arterial pressure but that of 120 kPa pressure was more higher. The preimplant pressure distension was a possible significantfactor leading to excessive intimal hyperplasia of early and middle stage of autogenous vein grafts.
Objective To study the mechanism of restenosis of the vein graft and the effect of the grafting injury to the vein graft. Methods One side of the 36 healthy rabbits was randomly chosen as the V-A group, and on the side a 1.5cmlong femoral vein was obtained, and an 0.5-cm-long segment of the obtained femoral vein was separated as the control group. The remaining 1-cm-long femoral vein was inverted and was autogenously implanted into the femoral artery on the same side of the rabbit. The other side of the rabbits was chosen as the V-V group, and on this side a 1-cm-long femoral vein was obtained ex vivo and then was sutured in situ. The vein grafts on both sides were harvested 4 weeks after operation. The specimens from the harvested vein grafts were stained with HE and theelastic fiber Victoria blue for an observation on the histological changes in the walls of the vein grafts, and the specimens were also stained by the immunohistochemistry of the proliferating cell nuclear antigen (PCNA) for an observation on the wall cell proliferation of the vein grafts. The changes in the ultrastructure of the proliferated wall cells of the vein grafts were observed under electron microscope. The two sides of the rabbits were compared. Results The smooth muscle cells of the media developed hyperplasia, but theintima and the media remained unchanged in their thickness (3.50±0.41 μm, 12.23±1.59 μm) in the V-V group, with no difference when compared with the control group (3.40±0.37 μm, 12.14±1.62 μm); however, when compared with the V-A group (25.60±3.21 μm, 21.30±2.47 μm),there was a significant difference in the thickness (Plt;0.01). There were no cells positive for PCNA by the immunohistochemistry examination in the control group. The cells positive for PCNA were found in the intima and the media in both the V-V group and the V-A group; however, the percentageof the cells positive for PCNA in the intima and the media was significantly greater in the V-A group than in the V-V group (16.4%±1.9% and 36.5%±3.7% vs 5.9%±1.3% and 23.4%±3.4%, Plt;0.01). In the V-V group, the endothelial cell could be observed under transmis-sion electron microscope, which was flat and had a processlike villus at its free end, and the endothelial cells were closely arranged andhad hyperplasia of the smooth muscle cells in the media. But in the V-A group,the endothelial cells had an obvious hyperplasia with an irregular shape and a widened space between the cells, and in the intima a great amount of the smooth muscle cells could be observed, which had a broken basement membrane. The smooth muscle cells also had an obvious hyperplasia in the media. The shape and alignment of the endothelial cells in the control group were similar to those in the V-V group, but the hyperplasia of the smooth muscle cells was not observed in the media. Conclusion The grafting injury can cause hyperplasia ofthe vascular wall cells, and if the hemodynamics is changed simultaneously, more serious hyperplasia and cell migration can be observed from the media to the intima, resultingin restenosis of the blood vessels. So, if we can reduce the grafting injury and improve the microcirculation of the vein graft, we may find out the methods ofpreventing restenosis of the vein graft. The animal model of the V-V graftcan help to understand the mechanism of restenosis of the vein graft.
In order to develope a new method to overcome the difficulties in anastomosis of blood vessels with different diameter, phleboplasty was utilized at the join-point to expand the diameter of branched vein graft, with a funnel-shaped stoma formed consequently. After successfully experimented in fresh blood vessels in vitro, the method was practised clinically to repair injured arteries in extremities, with the outcome that phleboplasty of branched vein graft could enlarge the diameter by 1-1.25 times, and with satisfied effects in 3 clinic cases. So, the conclusion was that: phleboplasty of branched vein graft was a new effective and convinient method to repair injured arteries with different diameters
Objective To repair defects at both ends of theblood vessels with a considerable disparity in the diameter of the both sides or with a large diameter in extremities by phleboplasty of branched and double autogenous veins. Methods Three kinds of phleboplasties——funnel-shaped, raincape-shaped and transposed Y-shaped were designed. Experiments in fresh blood vessels in vitro were completed successfully. These methods were used clinically to repair injured external iliac veins, femoral arteries and veins, and popliteal arteries and veins, to replant severed fingers and to transplant toenail flaps on thumbs by harvesting autogenous great saphenous veins,small saphenous veins and forearm veins in 36 cases, including 35 cases in emergency operation and 1 case in selective operation.The length of grafted blood vessels ranged from 1.0 cm to 15.0 cm. Results The phleboplasties of funnel-shaped could enlarge the diameter by 1.0-1.25 times inanastomotic stomas. The phleboplasty of raincape-shaped could enlarge the diameter large enough to meet the demands for various blood vessels in extremities. The phleboplasty of transposed Y-shaped could provide large vein transplants. In36 grafted veins, 35 were in patency. The blood supply in extremities was normal.ConclusionThe funnel-shaped and raincape-shaped phleboplasties of branched veins can enlarge the anastomotic stomas of grafted veins. The transposed Y-shaped phleboplasty of double femoral veins is an ideal way to repair injured primaryblood vessels with a considerable disparity in the diameter of the both sides or with a large diameter in extremities.
Objective To construct vectors that express phosphatidylinositol-3-kinase, catalytic, beta polypeptide （PIK3cb） shRNA in eukaryon plasmid catalyzed by PI3K in rat, then test their effects on intimal hyperplasia in transplanted vein graft. Methods One hundred and fifty SD rats were randomly divided into six groups （n=25, in each group）: blank (25% Pluronic F-127), shRNA-1, shRNA-2, 1/2 （shRNA-1+shRNA-2）, negative control (pGenesil-1 scramble shRNA) and positive control （wortmannin） group. The jugular vein in rats were interpositioned autologously into the common carotid artery. shRNA and 25% Pluronic F-127 were mixed and coated around the transplanted vein in three PIK3cb shRNA groups. Every 5 samples were removed according to the time point (1, 3, 7, 14 and 28 days after operation), respectively. The thickness of intima and neointima area were calculated and analyzed by computer system. The PCNA expression was detected by Western blot and SP immunohistochemistry. Results The intimal thickness of three PIK3cb shRNA groups were lower than those in the blank group and negative control group on day 3, 7, 14, 28 after operation (P＜0.05); The neointima area in three PIK3cb shRNA groups (except shRNA-2 group on day 3, 7) began to decrease significantly from day one (P＜0.05). The protein expression of PCNA in three PIK3cb shRNA groups on day 3 after operation were decreased compared with blank group and negative group (P＜0.05). The percentage of the PCNA positive cells area in three PIK3cb shRNA groups were significantly lower than those in blank group and negative control group in each time point (Plt;0.05). There were no significant differences between blank and negative control group in different time points (Pgt;0.05). Conclusion The PIK3cb shRNA can effectively inhibit the proliferation of vascular smooth muscle cell, which may provide a new gene therapy for the prevention of vein graft restenosis after bypass grafting.
Objective To investigate the results and applicationvalue of crotch-shaped vein grafts in repairing defects of the vessels with a large diameter.Methods From June 1998 to October 2003, 35 cases of vesseldefects with a large diameter were repaired with crotch-shaped vein graft (29 males and 6 females,aged 18 to 45 years with an average of 25.7 years ). The locations of defects were femoral artery in 25 cases, popliteal artery in 2 cases, femoral vein in 7 cases, and subclavian vein in 1 case. The interval between injure and operatioinwas 1-8.5 hours (4.1 hours on average).The blood flows of trouble and healthy vascular were determined with Doppler detector and compared preoperatively andpostoperatively. Results All the anastomotic stomas were patent in 35 cases. Thirty-one cases were followed up 6 weeks to 24 months (9.5 months on average), the patent rate was 100%, no case occurred vasospasm or tromboembolism; 2 cases occurred stomal leak and became hematoma, 3 cases occurred muscular necrosis, and the 5 cases achieved primary healing after secondary operation. The Doppler results showed that there was statistically significant difference in the blood flow betweenpostoperation and preoperation (Plt;0.01), but no statistically significant difference when compared the trouble vascular after operation with healthy vascular (Pgt;0.05). Conclusion The methodof crotch-shaped vein grafts is safe and effective in repairing defects of vessels with a large diameter,which is easy to draw materials and handy to operate. It has a promising value in clinical application.
Abstract In order to determine the fasibility of reestablishment of circulation with cryopreserved microvenous allografts (1.0～1.4mm in diameter), 40 rabbits were divided into 2 groups. In the control group, the fresh autografts were used. In the experimental group, 20 rabbitsfemoral vein segments were treated by a two-step freezing procedure. After stored in liquid nitrogen for 48 hours, the segments were implanted into the femoral veins as allografts. The histological as well as the pathological studies were performed with light and electron microscope, and its patency was determined by angiography. The results showed that the preservation of vein was generally good. The rejective response was weak. The patency rates of 1 week and 12 weeks were 90% and 85% respectively, and there was no significant difference with that of the allogenic fresh autografts (Pgt;0.05). It was suggested that clinical use of cryoperserved allogenic microvein grafts instead of fresh autografts was possible.
ObjectiveTo investigate the application value of the intravenous indwelling needle in radionuclide imaging examination.
MethodsA total of 120 patients underwent single photon emission computed tomography for bone and kidney dynamic imaging between October 2012 and April 2013 were randomly divided into group injected by venous indwelling needle (observagtion group) and group injected by traditional steel needle (control group), with 60 cases in each. We calculated the one-time success rate of venipuncture, the leakage rate of intravenous injection, residual radioactive dosage within the syringe and average exposure time of medical staff to radionuclide in the two groups of patients.
ResultsThe one-time success rate of venipuncture in observation group was similar to that in the control group (P > 0.05). During the injection, no leakage was found in observation group, while 4 leakage in 37 patients underwent bone imaging and 3 leakage in 23 patients underwent kidney dynamic imaging in the control group were found; there was no significant difference between the two groups (P > 0.05). The residual radioactive dosage within the syringe in observation group was lower than that in the control group, and the exposure time of medical staff to radionuclide in observation group was also lower than that in the control group (P < 0.01).
ConclusionsIntravenous indwelling needle for venous puncture can avoid leakage of radioactive imaging agent, reduce the residual radiological dosage within the syrings, increase the one-time puncture success rate and imaging resolution of dynamic scan, and improve the diagnostic accuracy and work efficiency effectively. Besides, the intravenous indwelling needle technique can reduce average exposure time of medical staff to radionuclide, acheaving the goal of optimized protection.
OBJECTIVE: To investigate the relationship between the different defect length of vessels and the options of vascular repair, and to compare the different options of repair because of the longitudinal biomechanical effect. METHODS: A clinical analysis was undertaken to evaluate the major arterial and venous injuries in human extremities repaired by end-to-end anastomoses or venous autograft(177 cases, 185 vessels). Compared the defect length of the same kind of vessels repaired by different options (Student-t test). Evaluated the defect length to repair arterial injuries between by end-to-end anastomoses and by vein graft by means of 95% confidence interval. RESULTS: There was significant difference between the defect length of brachial artery repaired by end-to-end anastomosis and femoral artery and popliteal artery repaired by autogenous vein graft (P lt; 0.01). The upper limit of confidence interval in the defect length of brachial artery, femoral artery and popliteal artery was 3.17 cm, 2.81 cm and 2.44 cm respectively by end-to-end anastomosis by means of 95% confidence interval. The lower limit of confidence interval in the defect length of brachial artery, femoral artery and popliteal artery was 2.82 cm, 2.41 cm and 2.17 cm respectively by vein graft by means of 95% confidence interval. The defect length of brachial artery, femoral artery and popliteal artery repaired by vein graft was linear correlation with the length of graft. CONCLUSION: Because of the longitudinal biomechanical difference of arteries and veins in human extremities, different options of repair are necessary to different arterial injuries.
Objective
To explore the ocular clinical features in patients with cranial venous sinus thrombosis (CVST).
Methods
The clinical data from 118 inpatients with CVST diagnosed by digital subtraction angiography (DSA).The patients included 53 males and 65 females with the sexual rate of1 :1.2. The initial onset age of the patients ranged from 15 to 67; 20-45 are the most common onset ages, and 30-40 reached the peak. The CVST patients were divided into 3 groups a c cording to the onset styles, including acute onset (within 2 days), subacute ons et (2 days to 1 month), and chronic onset (more than 1 month). The features of o cular and systemic manifestations was analyzed. A total of 58 out of 118 patient s with CVST were followed up for about 1 year after the diagnosis and treatment.
Results
Among the 118 patients with CVST, 25 (21.2%) had the ocular symptoms as the initial onset, 36 (305%) had ocular syndrome with other symptoms, and 57 (48.3%) had non ocular symptoms. There was no statistical significance among each group. The most common chief complains were the blurred and decreased vision (in 61 eyes, occupying 85.9% of all the chief complains). The most common symptom was papilloedema (in 57 eyes, accounting for 48.3% of all the patients with CVST). In 58 follow-up patients, 13 (22.4%) had serious visual decrease due to the optic atrophy. All the ocular manifestations related to the intracranial hyper tension caused by CVST.
Conclusions
In patients with CVST, 1/3 have ocular symptoms, and 1/5 have ocular symptoms as the initial manifestation. Visual decrease and papilloedema are the common symptoms in patients with CVST. We should especially advert to the patients with intracranial hypertension with unknown origins.
(Chin J Ocul Fundus,dis,2006,22:373-375)
